a,y/5+9/2=6/7.36/49 b,x:3/4+1/4=-2/3 c,1/4+1/3:(2x-1)=-5 d,(x.44/7+3/7).11/5-3/7=-2

`a, y/5 + 9/2 = 6/7 . 36/49`

`y/5 + 9/2 = 216/343`

`y/5 = 216/343 - 9/2`

`y/5 = -2655/686`

`y = -2655/686 . 5`

`y = -13275/686`

Vậy `y = -13275/686`

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`b, x : 3/4 + 1/4 = -2/3`

`x : 3/4 = -2/3 - 1/4`

`x : 3/4 = -11/12`

`x = -11/12 . 3/4`

`x = -11/16`

Vậy `x = -11/16`

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`c, 1/4 + 1/3 : ( 2x - 1 ) = -5`

`1/3 : ( 2x - 1 ) = -5 - 1/4`

`1/3 : ( 2x - 1 ) = -21/4`

`2x - 1 = 1/3 : (-21)/4`

`2x - 1 = -4/63`

`2x = -4/63 + 1`

`2x = 59/63`

`x = 59/63 : 2`

`x = 59/126`

Vậy `x = 59/126`

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`d, ( x . 44/7 + 3/7 ) . 11/5 - 3/7 = -2`

`( x . 44/7 + 3/7 ) . 11/5 = -2 + 3/7`

`( x . 44/7 + 3/7 ) . 11/5 = -11/7`

`x . 44/7 + 3/7 = -11/7 : 11/5`

`x . 44/7 + 3/7 = -5/7`

`x . 44/7 = -5/7 - 3/7`

`x . 44/7 = -8/7`

`x = -8/7 : 44/7`

`x = -2/11`

Vậy `x = -2/11`